Three bugs:
- Kernel 6.12.19 does not boot
- Libreoffice a) save as does not work correctly b) export as PDF does not work
Just tested.
I don’t have any problems with the quoted tasks above, though I am on kernel 6.6.
If you refer to Libreoffice Writer: for me, both Save As and Export as PDF, works fine ( Version 24.8.5-4)
Saving and do an export does not work the second time.
Test case:
open two or more letters, then execute save as or export as pdf for these letters and then Libreoffice crashes.
Just did your test case on three different ODT files, and LibreOffice Writer (24.8.5.2) didn’t crash here!
Manjaro Stable, DE Cinnamon, Kernel 6.12.19.
Tested on my latest update (KDE, Wayland) and LibreOffice Writer and Calc work as expected. No issues here
Still not reproducible for me, and in the meantime I am however sorry for the issue you are having 
Maybe is better if you open a dedicated thread for the issue, outside of the thread of the Stable announcement.
Indeed. I’ve moved the discussion to a new thread. 
Even though @Keruskerfuerst claims he is a jelly donut1 
on his profile, I know he knows better since he’s been around long enough to be familiar with the following:
1 ich bin der Berliner !
Regarding the first descriptive item;
There is already a separate thread;
…currently with posts reaching the low 60’s.